This statement is hysterically ahistorical. Each thing you listed had active moderation. Sysops didn't just allow anything on a board, if you posted stuff off topic or offensive (to the Sysop) it was removed with prejudice. IRC networks all had long lists of k-lines of people kicked off the network. Individual channels had their own mods with ban lists. Forums either moderated or were deluged with spam. AOL and ICQ were both highly moderated.
Just like today small networks might be uncensored free-for-alls. Even then they are/were rarely actually uncensored, it's just you might have not been censored because you aligned with the views of the owners/operators.
The only really uncensored free-for-all was Usenet and that state only existed for its first decade or so when it was limited to professionals and academics. The Eternal September turned Usenet into an unusable mess. It's corpse limps along today as a vehicle for piracy and not much else.